Attachment for sewing machines



Jan. l1, 1938.A s. M. cREwDsoN 2,105,184

` uATTACHMNT FOR SEWING MACHINES Il Filed Feb. 28, 1935 2 Sheecs--SheetI l j@ l IHHHII i v 1 IIIV w l 61 @E 66 Lag .11 5055 J5 Z0 57 v6559- Jan. 11, 1938. s, M, CREWDSON I 2,105,184

ATTACHMENT FOR SEWING MACHINES Filed Feb. 28, 1935 2 Sheets-Sheet 2 fnl/75%" h Jara/ZM Crea/50m Patented Jan. 1v1, 1938 ATTACHMENYTJFOR SEWING MACHINES Sarah M. Crewdson, Chicago;` `Ill., assigner of one-third to Robert H. Goedhart, Chicago, Ill.

Application February 2s, 19735, serial No. 8,626

13 claims; (Cr.- 11a- 124) The invention relates `to an attachment for sewing machines and has for its object to provide an attachment that will triml a seam by cutting the material to form either a straight edge 5 or an irregular edge at a predetermined distance from the seam.

Another object of the invention is to provide 'an attachment of the character described thatA can be readily secured to-a sewing machine Vin a plurality of adjusted positions with respect to the needle to permit the operator to vary thev distance of the severed edge from the stitching, thereby cutting margins of variable widths.

Another object resides in the provision of an attachment that will embody novel means for operating the same from the reciprocating needle post of the sewing machine and which means will synchronize the cutting element with the feed mechanism of the machine vso that the rate of travel of the material through the machine will be the same as that through the attachment.

Another object of the invention is to provide an attachment such as described which will accommodate thin material and also heavier thick Y material having resilient means for maintaining y the proper pressure on the material during the cutting operation. g f

Another object of the invention is to provide an attachment having a rotary cutting element which can be readily replaced by a rotary pinking element when it is desired to trim the edge with an irregular design.

The invention also contemplates the'provision Y o feed rollers for feeding the material through the attachment and novel mounting means for the lower feed rollers, whereby one of said rollers is resiliently held in engagement with the cuttingV t more fully described and particularly pointed out in thespecication, drawings and claims appended hereto.

y In the vdrawings which illustrate an embodiment of the invention and wherein like reference characters refer to like parts--l for severing the material on a straight edge and Figure 1 is a plan view'of the attachment constructed in accordance with the invention `and shown in association with the operating elementsy of a` sewing machine; Y

Figure 2 is a side elevational view of the attachment of Figure l showing a pinking element with feed rollers cooperating therewith;

Figure 3 is a side elevational view of the attachment of Figure l, showing the operating mechanism for connecting the rotary cutting elementwith the sewing machine;

Figure 4 is a bottom plan view of the attachment; l

Figure 5 is a sectional lView taken-substantially l along line 5 5 of Figure 4 showing a pinking element in contact with the feed roller and aprons for directing the material into engagement therewith;

Figure 6 is a detail sectional view taken along line 6 6 of Figure 2;

vFigure 7 isa detail sectional view taken alongline l--l of Figure 5; and

Figure 8 is a'sectional view similar to Figure 'l but showing a rotary cutting element in association with the feed rollers.- I The present invention particularly relates to improvements over the form of mechanism for trimming seams shown in my copending application, Serial No. 743,642, filed September l12, 1934.' t

Referring to the'drawings, the attachment has been shown in associated relation with certain operating parts of a sewing machine of the typeadapted for home use and which consists of a` work supporting surface li), a vertical reciprocating needle post il carrying a needle i2, and a supporting post i3 having the foot Hl secured thereto by the thumb screw l5 and which holds the material to be sewed in contact with feeding mechanism i6 of the sewing machine. It is to be understood that the supporting post I3 can be vertically reciprocated by the operator and is yieldin'gly held in contact with the material during the sewing operation, being lifted by the operator to remove the same from the material at the end of the sewing operation.

The attachment essentially consists of a frame member, Figure l, which includes'a vertical'supporting member I8, having an inclined working surface 20'secured thereto. Extendingironi one side of the member l8is a boss 22 overlying but being spacedfrom the working surface as `b-est shown in Figure 6. Extending from the member |-8 below the working surface are two spaced bosses 23, Figure 7, and 24, Figure 6, which bosses journal shafts to be presently described. The right angled strap members 25 and 26 are suitably bolted to the lower portion of wall I8 and to the surface 20, said strap members thereby supporting said surface from the member. Adjacent the base of said member and to the rear thereof is provided a laterally extending foot portion 21 which extends for part of the distance of the surface 20 to aid in supporting the frame in hori- Zontal position on the surface l0 of the sewing machine.

The boss 22, Figure 6, journals a shaft 28 which projects from the end of the boss for receiving the washer 3B, the cutting element 3| and retaining member 32, the parts being keyed and held fixed to said projecting end of the shaft by the bolt 33. The opposite end of shaft 28 projects from the wall I8 to which end is fixedly secured the ratchet wheel 34. Rotatably mounted on the end of shaft 28 projecting beyond the ratchet wheel is an operating arm 35 having the stud 36 integral therewith and which is held on the shaft by the bolt 31. The cutting element may take the form of a pinking knife for cutting an irregular edge or a cutting blade for severing the material along a straight edge.

One end of the operating arm, Figure 3, has the pawl 38 pivoted thereto as at 39 and which is held in contact with the ratchet wheel 34 by the coil spring 40. The other end of operating rod 35 is bent at right angles forming an intermediate section 4|, shown in Figure 1, and which section is further bent and turned downwardly, forming the portion 42 having a recess for engaging the stud 43. Said stud has a knurled end 44 and is suitably secured to the reciprocating needle post of the machine.

From the foregoing it will be understood that vertical movement of the needle post will oscillate arm 35 to cause engagement of pawl 38 with ratchet wheel 34, causing rotation of said ratchet wheel and shaft 28 in a counter-clockwise direction, Figure 3. Rotation of the shaft'28 by the reciprocating element of the sewing machine will therefore rotate the cutting blade of the attachment. A locking dog 45 is provided, pivoted to the wall at 46 and yieldingly held by spring 49 in contact with the ratchet wheel, in order to prevent reverse rotation of said ratchet wheel. However, the degree of oscillation of the arm 35 is in excess of that required to rotate the cutting element in synchronism with the feeding mechanism of the sewing machine, and accordingly the invention has provided means for disconnecting pawl 38 from the ratchet wheel at the end of the Y downward stroke of the arm. Said pawl carries at its extreme outer end the pin 41 and the wallY I8 has suitably secured thereto an abutment 48v which is adapted to engage the pin to throw the pawl upward out of contact'V with the ratchet Wheel. Thus the arm 35 has operative connection with ratchet wheel 34 for only a part of its downward stroke and by properly positioning abutment 48 the throw-off pawl 38 can bev timed so as to accurately synchronize the speed of rotation of the cutting element with the feeding mechanism of the sewing machine so that just the amount of material supplied by the sewing machine is fed through the attachment. It will be understood that where it is possible to lengthen the arm 35 by locating the attachment" further to the rear of the needle that the throw-off for the pawl can be dispensed with since under these conditions full engagement thereof for'the downward stroke of the arm will befnecessary to rotate the cutting element at the proper speed. The invention also contemplates that the ratchet wheel 34 may be` reduced in size and pivot 39 of pawl 38 relocated to secure the correct speed of the cutting element.

The work supporting surface 2U is provided with an opening directly below the cutting element 3|, Figure 5. Part of this opening is closed by a rear apron 50 which is suitably secured as at 5| to the underside .of surface 20. Forward of said opening there is provided a front apron 52 also suitably secured to the underside of surface 2l), the free edge of said apron resting on the lower feed rollers 53 to direct the material between said cutting element and the feed rollers. Said feed rollers are journalled in a yoke 54 by means of the stud 55 passing through the arms of said yoke and which stud at its inner end is cut away on its lower side providing the flat surface 56, as shown in Figure 5. The yoke 54 is provided with a shaft 51 which is journalled in boss 23 of the vertical wall I8, the other end of said shaft extending beyond the boss and receiving the coil spring 58 which is retained thereon'by the washer 59 and bolt 60. The coil spring therefore yieldingly holds the yoke in contact with the end of boss 23. The shaft 51 however mounts the yoke within the frame so that the same may have rotation, thereby supportng the feed rollers 53 for bodily movement in a direction toward and away from the cutting element. Movement of the feed rollers in this manner is desirable as it is necessary that the attachment accommodate thin, light material as well as heavy, thick material, and in order to apply the proper pressure on the material for :i

feeding the same, a resilient member 6| is provided, said member having one end xed to support 62 and its other end in engagement with the yoke 54. Y

By reason of the resilient member 6| the feed rollers will be yieldingly held in contact withthe cutting element 3|. However, for starting Ythe material through the attachment it is desirable that the feed rollers be located out of engagement with the cuttingrelement so that the material may be easily positioned therebetween. For accomplishing this a release lever B3 is provided, Figure 3, having the stud shaft 64 secured thereto, and which is mounted in the frame i8. Said stud shaft has xed thereto on the opposite side of the frame the arm 65, Figure 5. Said armoverlies the projecting end of shaft 55 which journalsY the feed rollers so vthat actuation of lever 63 inA a direction to impart clockwise rotation to arm 65 will rock the yoke 54 in a dovmward direction, moving the feed rollers out of I contact with the cutting element. The cutting element 3| contacts the periphery of the inner feed roller and as the material passes between these two elements the same is severed, forming an irregular or pinked edgercorresponding with the design of cutting element. For this operation it is necessary to lock the feed rollers against bodily movement as above described, since the severing of the material by element 3| would be impossible if the feed roller could be depressed. The locking means consists of an eccentric 66 carried by shaft 61 which is journalled in the boss 24 on the frame. On the opposite end of shaft', 61 is suitably threaded a knob having a knurledportion 68Y and a collar 10 which is flattened for a portion of its periphery and against which rests the strip of spring metal 1|, Figure 3. The supportingY Vstud 12 projects from the frame and'positions said metal strip so that pressure groener,

rection downwardly and therefore said rollers provide a rm kand unyielding surface` for the cutting element.` l f In addition to trimming seams with'J an irregular design, which is accomplished by the pinking attachment 3l, the .present device is also v capable of trimming said seams on a straight edge. The invention contemplates that the element 3l may be replaced by the upper feed roll` ers 53 and cutting blade 13. Figure 8 shows the association of the: feed rollers with respect to the cutting blade, it being understood that the parts are keyed to the shaft 28 and retained thereon by bolt 33 which likewise retains the element 3l thereon. The yoke 54 has been previously described as journalled in boss 23 in a manner permitting axial movement against the tension of the coilfspring 58. This construction has been provided in order to yieldingly hold' one of the lower feed rollers 53 against the surface of the cutting blade 13, asv shown in Figure 8. When the cutting blade is associated with the feed roller in this manner the parts effectively perform a cutting operation, severing the material with a clean cut forming a straight edge. `When thecutting blade hasbeen substituted for the pinking element the locking, eccentric 66 is rotated to position the same out of Contact with shaft so that the yoke and the lower feed rollers have bodily/movement, being yieldingly held in contact with the upper feed rollers located on the respective sides of the cuttingblade. As shown in Figure 8, said upper feed rollers are equipped with rubber tires 14. It is not absolutely necessary that the tires be composed of rubber as any friction material will function just as satisfactorily. rIhe main object of surfacing the periphery ofthe upper feed rollers in this manner is to insure positive feed of the material through the attachment.

The attachment is held in' adjusted position on the surface IB of the sewing machine by means of the scale 15 having graduations thereon and being provided with an elongated slot 16. The member I8 is reduced in height at the end adjacent the supporting post I3 and is provided with a projecting screw 11 having the winged nut 18 thereon, the screw extending` through the.

slot in the scale,'which is then held to the attachment by the winged nut. The scale 15 terminates in the upwardly bent portion 19, Figure 2, to which is pivotally secured a bent member 35 which may be considered as a separable part of the scale. Member 8@ is bent at one end to form a U-shaped portion which is adapted to overliethe secured portion of the foot I4 so that the foot and member are releasably secured to the supporting post i3 by the thumb screw l5. When the separable parts of the scale are rigid with each other vibrations from the sewing machine are readily transmitted to the attachment and in order to reduce these vibrations to a minimum the invention pivotally secures the separable parts of the scale to each other by the stud 8|, whichreceives the coilV spring 82 for yieldingly holding the parts together. ofthe pivotal relation between the parts of the scale the foot I4 can be raised by the operator alimited extent to adjust the material being sewed Without detaching the part 15 of the scale from the attachment. This operation is necessary when it is desired to raise the foot i4 for its full height.

Figures 1 and 2 show 'a guard`83 for protecting the fingers of the operator from contact with the cutting element. Said guard is Vpivoted at 84 to a portion 85 secured to member iS. rlIhe pivot 84 is provided with resilient means to yieldingly maintain the guard in horizontal position with the stop 8G in contact with the frame member as shown in Figure 6. This construction holds the guard in position for protecting the operator but can be easily lifted when it is desired to remove the cutting element from the attachment and replace vthe same with a cutting element having other and different characteristics.

Projecting from frame i8 is a rod 81, as shown inFigure 1, to which is adjustably secured member 88, said member being adapted to be held in position on said rod by tightening of the screw 90. 4The member forms a support for the materialguide SI. to assist the. operator in guiding the same from the needleof the sewing machine to the cutting mechanism of they attachment. In the operation of cutting the material por-V tions thereof nd theirway between the lower feed rollers Y53. If the lint and scrap pieces of material are not removed from between the feed rollers they soon interfere with the operation of the same. For this purpose the invention provides a stripping finger 52, Figure 2, suitably secured at one end to foot portion 21 having its free end located between the feed rollers 53. The nger is preferably of spring wire so that the same maintains its position between the feed rollers, whereb-y the pieces of material and lint are effectively removed.

The invention is notV to be limited to or by details of construction of the particular embodiment thereof illustrated by the drawings, as various other forms of the device will of course be Yapparent to those skilled in the art without dethe needle, means for adjustably securing the at,

tachment to said scale, and means provided on the scale for absorbing the vibrations of the sewing machine whereby they are not transmitted to the attachment.

2. An attachment for sewing machines comprising a rotary cutting element, means operatively connecting said element with a movable member of the sewing machine whereby said element is rotated by the action of the machine, a scale adapted to be secured to a member of the machine and extending laterally with respect to the needle, and means for adjustably securing the attachment to said scale, said scale comprising two sections pivotally secured together whereby the vibrations of the sewing machine are not transmitted to the attachment.

By means 3. An attachment for Vsewing machines' com; prising a rotary cutting element, means opera-v tively connecting said element with a movable member of the sewing machine whereby said element is rotated by the action of the machine, a scale adapted to be secured to a member of the machine and extending laterally with respect to the needle, and means foradjustably securing the other end of the scale to said attachment,

said scale having a yielding joint intermediate its ends for absorbing the vibrations of the sewing machine whereby they are not transmitted to the attachment.

4. An attachment for sewing machines, comprising a frame member having a rotary cutting element, a feed roller positioned below' the cutting element, means journalling said roller and being mounted in theframe for movement in a direction parallel to the axis of the roller, and means biasing the mounting means in a direction tohold the feed roller in engagement with the cutting element for performing a cutting operation.

5. An attachment for sewing machines, comprising a frame member, a shaft mounted for rotation in said member and carrying a cutting blade, a feed roller positionedV below said bladeV means to maintain the cutting blade and roller in contact.

6. An attachment for sewing machines, comprising a frame member having a rotary cutting element, a feed roller positioned below the cutting element and having contact therewith for performing a cutting operation, means journalling 40 `the feed roller, a shaft carrying said means and being mounted in the frame for movement in a direction parallel to the axis of the roller, `and resilient means on the shaft for biasing the journalling means in a direction to'hold the feed uroller in contact with the cutting element.

7. An attachment for sewing machines, comprising a frame member having a rotary cutting element, a roller positioned for contact with the cutting element, means journalling said roller, a

oshaft carrying said journalling means and being mounted in the frame for rotation, resilient means forcing the roller into Contact with the cutting element, and a manually operable lever for holding the roller out of contact therewith.

8. An attachment for sewing machines, `com prising a frame member having a rotary cutting element, a roller positioned for contact with the l cutting element, means journalling said roller, a'v shaft carrying said journalling means and being contact with the cutting element, and a manually' operable lever adapted to engage the journalllng means to depress the same against the tension of the resilient means.

9. An attachment for sewing machines, comprising a frame member having a rotary cutting element, a roller positioned below the cutting element, a yoke journalling the'roller and being rotatably mounted in the frame, whereby said roller is supported for bodily movement, resilient means forcing the yoke upward to hold the roller in contact with 'the cutting element, and a lever adapted to be manually actuated forholding the roller out of contact with the cutting element.

10. An attachment for sewingv machines, comprising a frame member having a rotary cutting element, a roller positioned below the cutting element, a yokejournalling the roller and being rotatably mounted in the frame, whereby said roller is supported for bodily movement, resilient means yieldingly holding the roller in Contact with the cutting element, and a manually operable lock for lockingthe yoke preventing downward movement of-the'same.

l1. An attachment for sewing machines, comprising a frame, a shaft journalled in the frame and carrying a cutting blade, feed rollers fixed to the shaft and positioned on the respective sides of the blade, lower feed rollers located below the blade, a yoke journalling the lower feed rollers and being rotatably mounted in the frame, whereby said rollers are supported for bodily movement, and resilient means biasing the yoke to yieldingly hold the lower feed rollers in contact with said first mentioned feed rollers.

12. An attachment for sewing machines, com'- prising a frame, a. shaft journalled in the frame and carrying a cutting blade, feed rollers fixed to the shaft and positioned on the respective sides ofthe blade, means' rotating said shaft whereby said feed rollers are driven, lower feed rollers located below the blade, a yoke journalling the lower feed rollers and being rotatably mounted in the frame, resilient means yieldingly forcing the yoke upward to hold the lower feed rollers in contact with the driven rollers, and a lever adapted to be manually actuated for holding the lower rollers ou-t of contact with said driven rollers.

13. An attachment for sewing machines comprising, a rotary cutting element, a rotatable shaft therefor, means operatively connecting said cutting elementwith a reciprocating member of the machine whereby said element is rotated by the action of the machine, said means including a ratchet wheel fixed to said shaft, an arm pivoting on thershaft and carrying a pawl engaging the ratchet wheeLand an abutment for disconnecting the pawl for a part of the downward oscillating stroke of the arm.

SARAH M. CREWDSON. 

